This invention relates generally to improvements in medical swabs and the like of the type used for collecting biological specimens in the course of performing a variety of medical tests. More particularly, this invention relates to an improved and substantially self-contained specimen test unit having a swab member encased within housing components of blow molded plastic or the like, wherein the test unit includes improved means for handling one or more reagents and for delivering such reagent to the swab tip in the course of performing a medical analysis.
Medical swabs are generally known in the art for use in collecting biological specimens from a patient for further analysis. Such medical swabs commonly comprise a fibrous swab tip at one end of an elongated stick or shaft which is manually handled to contact the swab tip with selected tissue cells or other biological specimen obtained, for example, from within the ear, nose or throat of a patient. As a result, some of the targeted biological specimen adheres to the swab tip which can then be contacted with one or more selected reagents to indicate the presence of infection or other information regarding patient condition. Tests commonly performed with such patient specimens include, by way of example, fluorescent tests, enzymatic tests, monocolonal based tests, agglutination tests, and others.
In accordance with standard techniques, the collected biological specimen is normally transferred from the swab tip to a slide or other laboratory apparatus such as a test tube or the like for contact with the selected reagent and further analysis. However, it is frequently difficult to ensure transfer of a sufficient specimen quantity from the swab tip to the laboratory slide or test tube to ensure accurate test results. Moreover, in many instances, the collected specimen must be transported to a medical laboratory for performance of selected assays, but delays between the time of specimen collection and actual test performance can result in partial or complete drying of the specimen, with a corresponding decrease in test reliability.
Various swab-type collection devices have been proposed in efforts to provide enhanced contact between a specimen and reagent, or, in the alternative, to sustain the specimen during post-collection transport to a medical laboratory. Such swab collection devices have been provided in the form of a compact kit including a fibrous-tipped swab together with one or more reagents for contacting a specimen collected upon the swab tip. In some designs, the reagent is carried by a frangible glass ampoule which is broken at the appropriate time to release a reagent for contacting the specimen on the swab tip. The glass ampoule, however, comprises an additional and relatively costly component to the collection device or kit. Moreover, the glass ampoule produces sharp fragments when broken, wherein the collection device must be designed to prevent the glass fragments from contacting the collected specimen or medical personnel. Alternative swab collection devices have envisioned reagent placement within rupturable cells or compartments formed within a plastic swab housing. In these designs, the reagent cell or compartment is opened at the appropriate time to permit reagent flow into contact with the collected specimen on the swab tip. While this approach avoids the disadvantages associated with glass ampoules, the manufacture of plastic housings with liquid-filled compartments adapted for controlled rupture has been relatively difficult and generally unreliable.
There exists, therefore, a significant and continuing need for further improvements in swab-type specimen test units, particularly with respect to facilitated reagent delivery to a collected specimen on a swab tip, without requiring the use of reagent-containing glass ampoules or rupturable plastic compartments. The present invention fulfills these needs and provides further related advantages.